Synthesis of some new thiazolo[3,2‐ a ]pyridine, bi‐thiazole‐thiazole , bi‐thiazole‐pyrazole and bi‐thiazole‐thiophene derivatives

We reported here reactions of 2‐bromo‐1‐(4‐methyl‐2‐(tosylamino)thiazol‐5‐yl)ethanone 1 with 2‐cyanoethanethioamide afforded new 2‐cyanomethylthiazole derivative. The reaction of the latter with arylidenemalononitrile derivatives afforded thiazolo[3,2‐ a ]pyridine derivatives. Also, compound 1 was subjected to a one‐pot four component Gewald reaction with molecular sulfur, malononitrile and aromatic aldehydes in the presence of L‐proline afforded 2‐aminothiophene derivatives. The structure of the newly synthesized compounds was established based on its elemental and spectral data.